Shock absorber



3 Sheets-Sheet l Humm, s

APH] 11 1933 c. H. FOSTER shock ABsoRBER Filed June 16I mlv 6.. l mu i...

C. H. FOSTER SHOCK AsoRBER April 11, 1933.

, 1928 5 Sheets-Sheet 2,

Filed June 16 lill am g

April 11, 1933. C. H. FOSTER 1,903,423

SHOCK ABSORBER Filed June 16, 1928 '3 Sheets-Sheet 5 Patented Apr. 11, 1933 CLAUD H. FOSTER, oF wrcxmrrnomo f snoek ABsoRBER appiiation mea AJune is,

This invention relates to shock absorbers such as are interposed between the axles and bodies of automobiles for the purpose of checking relative movements therebetween due to the encountering of obstacles or depressions by the wheels.

The shock absorber herein shown consists generally of a brake drum with a composite 'brake band arranged externally of the drum,

and a strap operatively connected to the said band for operating the same, there being a helical spring connected with the band for taking in the slack of the strap and for moving the brake band therewith, as the vehicle members approach eachother.

It is the general purpose and object of the invention to provide a shock absorber lwhich is notonly sim le of construction and economical of ro uction, but which'will automatically e ect the gripping or braking action of the brake band upon the drum by the separation of the body and axle and which also will automatically effect the release of such gripping or braking action under conditions to be pointed out hereinafter.

A further object of the invention is to provide a shock absorber of this type which is capable of withstanding and accommodating all ordinary incidents of use. Further and more limited objects of the invention will appear hereinafter and will be realized in and through the construction and arrangement of parts shown in the drawings hereof, wherein Fig. l represents a sectional ele- Y vation of a shock absorber constructedin ac-` cordance with my invention, showing the parts in the positions which they occupy when the vehicle springs are compressed somewhat more than under ordinary or normal riding conditions; Fig. 2, a sectional View correspondingr to the line 2-2 of F ig. 1; Fig. 3 a View similar to Fig. 1, showing the parts in the positions which they assume when the axle and vehicle body have approached each other following a more severe compression ofthe vehicle springs; Fig. 4, a view similar to Figs. 1' and 3, showing the positions of the parts when the body and axle shall have separated a suiicient vdisp tance to'releasethe brakingaction; Fig. 5 a

192s. serial No. 255,910... Y

rear elevationo'the shock absorber shown inl the'preceding views,`with certain parts broken away; and Figs. 6 .and 7, detailsin sectional elevation showing modifications' of the brake band construction. 1

' Describing the various parts by reference characters, and first irl-connection with Figs.' Y 1 to 5, inclusive, 1 denotes one of the side frame members andf2. the axle -housing` of a vehicle. 3 Y denotes a cylindrical brake 0- drum Vhavinga-bottom orback wall, the central. portion 4 ofV whichA is oiisetfrom the peripheral portion 5,` such offset portion being .seated within ametal disk 6 having a rounded peripheral iiange 6a. The .brake drum is 65 secured to the side frame member 1 by means y of bolts, the Shanks of whichare indicated at 7 and which Shanks project through v.openings in theparts 1, 4` and `6.# `Eachboltis provided with an enlarged cylindrical head TQ 8 within the'body of the brake drum, the opposite ends of` th'ebolts beingv Ythreaded and provided withnuts 9 andy lockiwashers 10.\ a The bolt heads 8 `are provided each with 715 a transverse bore' 8a adapted-:to receiverthe inner. end .11a of avhelical spring 11; thereby to anchor the spring within thedrum. The outerrend 11" of the said spring fis secured tothe inner or rear face of the-fiat 8.0 front or outer plate 12 offthe outer .ycover member of a housing, whichcover member comprises the` said plate and a cylindricalwall 12a. The end 11b may' be secured to theV plate 12 in any. convenient manner,` as 85 by ymeans of one or more inner clamping members 13 having each a V-shaped groove at its center adapted to engage the saidend of the spring, the clamping members being riveted through the plate` 12 to a plate 14:` 90 on the front of the plate 12, which `plate 14 may be a name plate. V- The wall 12a ,telescopesover `a cylindrical wall `15 ofl the rearor inner housing` meme ber, `and thelatter wall merges `witha rear annular wall ,15a having VYits. 4inner edge' spaced `from the central `portion 4 of :the base ofthe brake drum; The rear .annular wall 15 is provided witha Vpair ovfjrear;U wardly or inwardly Vextending [annular 1,00

PATENT grooves 15b therein, each of which is adapted to receive a packing ring 16, which packing rings engage the portion 5 of the rear or inner Wall of the brake drum, ,therebyV to prevent the entrance ofV dust into the, interior of the housing which encloses the brake drum Vvand the brake band.y The entrance of dust is further prevented by means of the flanged disk 6, 6a. v Y p The housing constituted by theparts 12,

12a and 15, 15a is spaced from the'brake drum and is movable with reference thereto, for a purpose V to be explained hereinafter. Y k Y Y.

17 denotes a spring metal band having therewithin and attached'theretoa friction band 18,1the, said band being of any suitable material', such as Vfabric belting. The

springloand 17 is given afcurvature such that it tends'to hold the band 18 in'close engagement vWith .the outer. surface" of the drum 3S The composite band isn of such length that,fwhen applied ,to the' drum, its ends will be spaced apart. It isconnected atl one end tothe housing'vvall 15 bymeans of .rivets 19,fth'ere'being a Afiller strip 20'insertedbetween the band 17 and the inner face of the housing Wall, but the total thickness of the filler-strip andV of the bands 17 and 18 at this point is considerably less than the normal Widthof theYV space between-the brake drum andthe housing Wall 15,'so that this end of the brakeband is lifted clear of and'V spaced from the drum, as vshown particularly in Figs. 1, 2 and 4. The opposite end ofthe brake band is built up so as to fill, 4orY substantially fill, the space between thefbrake fdrum and 'the Wall '15. This building-up is eected by means of strips i 21fand 22 applied to the outer face of the Aband 18, the parts 17, 18, 21 and 22 being secured together Vby rivets 23.V One of the strips 21, 22lmust be yieldable, and for this Y purposeI prefer to make such strip vof soft rubber. The strip 21,k in this form ofm'y inl vention, is made of rubber, While the strip 22 is preferably lmade of fabric beltin'g.YV The built-'up'end--of the brake band is designated generally by the-"letter A and the opposite end is designated generally by the letter B.

Q For the purpose of causing thelbrake band to function through the separationV of the body andaxle, 'IV secure to the housing the upper V-end portion '24 of a strap C. This strapA isjconveniently secured to both Walls 12?N -and15 of the housing-by meanspofshort screw bolts 25 extending through al metal plate 26` on theouter surface of the Vstrap and" through openings in the Vhousing Walls 12"*x andl 15, their inner 'ends being' threaded intova curved metal plate-27 engaging the interior ofthe Wallli".v The'lower portion;

of'thenjstrap C isloopedvaround the axle housing2, and the extreme end 2li*L of such portiony is fastened to the body of thel strap' by means of a U-bolt 28, plates 29, and nuts 30 on the ends of the legs of the bolt.

In Figs.. 1 and 2, the parts A and B. are

shown as somewhat above the positions which they occupy during ordinary or normal riding. Owing to the fact that the housing floats with reference tothe brake drum, some vlight pressure will' bev exerted through the strap C and through the builtup yend A of the brake band upon the drum.

kThe opposite end-'B of the strap Will be free fromrthe drum, as explained hereinbefore. It Will be noted that, when in the position shownin Figs. 1 and 2, the brake band can travel yin a clockwise direction only a short distance before the strap- @will be substantially tangent to the surface of the-part of the housing immediately over such builtupend. The purpose ofthis arrangement Will be explained hereinafter.

1With the parts constructed and arranged as'described, when the-Wheels encounter an obstacle which moves the axle toward the body, the'spring 11 Will move the brake band freely in f a counter-clockwise direction around the brake drum, taking in the slack of tlie'strap C. No matter how rapid maybe ,the movementof the axle toward the body,

or vice versa, the spring is under vsufficient torsion to enable it immediately to fleet the brake band'around the drum and to take in the slack ofthe strap. .At the end offthis movement, the parts. may beapproximately in the lpositions shown in Fig. 3. On rebound, .or separation of the body and axle, the strap C, dueto the Heating of the housing` to Vwhich itis connected as: Well as. tothe somewhat yielding nature of the housing,

Will press the built-up end A'of the brake Y Would interferevvith ease of riding and WithY the desirable action of the'vehicle springs.

Therefore, as the built-up end A approaches Y a position Where the strap C becomes tangent tothe housing, the pressure of such end A of the band upon :the brake drum is. relaxed and, when thisk position of tangency 1is reached and the built-upend shall have passed beyondwthe point Where it can be pressed against the drum by the strap C,-

further separation will be resisted lonly by the vehicle springs and by the comparatively slight resistance aorded by thev spring 11.

rlh'e purpose of the yieldable cushion ,con-

and brakedrum, one or more lstop pads 31V of any suitable material (as fabric belting) may be applied to the interior of the housing, being of less, thickness Vthan f the average width of` thespace between the housing and the brake band. l

A further advantage of the construction and arrangement ofrparts shown herein :1s

that, when riding under normal conditions,

if one or more of the wheels of the vehicle should drop into a hole in the road, there will be practically no braking action, as the built-up end of the brakeiband is so located that itis not pressed against the brake drum by the brake band and passes below the point where such action can occur. This prevents the body `from being pulled down by `the axle, to the discomfort of thevoccupants of the vehicle.

Furthermore, because of the fact that the housing is movable or floats with reference to the brake drum andbecause of the fact that the metal of which it is composed is resilient, the end A of the brake band will always be in leffective engagement with the-L brake drum and the housing when thev body and axle are moving away from each otherup to the time when the end A shall have passed below the place at which it is subj ected to the pressure of the strap C.

In Fig. 6, there is shown a modification of the invention, wherein ythe cushions or pads 21 and 22 of the built-up end A of the brake band are reversed; in otherrespects the construction is the same as shown in Figs. 1.to 4 inclusive, and the operation of the device is substantially'the same as the operation of the device shown in said Figs. 1 to 4.

In Fig. 7 there is shown a still further modification of the invention,` wherein the building up ofthe end A2 of the Vbrake band is accomplished by inserting between the inner Wall 15 of the housing and the band 17 a flat spring 31a having an intermediate arch adapted to bear against the wall 15 and to bear at its opposite ends against the strip 17, one of such ends being secured to said strip and to the strap 18 by means of one or more rivets 32. Y

In describing the invention, it has been assumed, for convenience of description, that the brake drum and housing will be carried by one of the side frame members and that the strap C will be secured totheupp'er portion of the housing andlextend around such upper portion, with its lower end secured to the axle housing; and the terms upper and lower havebeen used' in connection with such description, but without any intention of limiting thereby the use of the invention to such specific location and arrangement of parts.

flexible member C as a strap, Ido not intend thereby to limit myinvention .to the use of any particular materialy `or' to any .particular shape of material which may be employed for such'strapk or member. V y The spring 11 is normally under light comel pression, as well as under torsion, whereby it presses the Apacking 16` against" the back wall 5 of the brake drum, thereby compensating for wear and preventingentrance of dust, etc. into the housing. Y

Having thus described Amy'invention, what Y Iclaimis:- H v. f 1. A shock absorber comprislng a brake drum adapted to be` secured to one of twoA Furthermore, while I4 have described thev the exteriorA of said housing and adapted to be connected at its otherend to the other vehicle member and arranged to engage' the outer surface of the housing, a spring having one end anchored with respect to the housing I and'its other end connected to said housing, and a brake band on the said drum having one end secured to the housingand having its opposite end in proximityV to suchlirstmentioned end, the second mentioned end of the brake` band substantiallylilling the space` between the brake drum and the housing and the firstmentioned end of the brake band being spaced from the brake drum, the saidV housing being mounted so as tobe movable toward the brake drum through the lplullof ,105

said strap upon said housing.

2. A shockabsorber comprising a brake drum adapted to be secured to one of two relatively movable vehiclemembers, a hous-2 ing surrounding the said drum' and spaced therefrom and movable toward and from theA drum, a strap connected at one end to the exterior of said housing and adapted to be connected at its other end to the other-vehicle member and Varranged to engage the outer surface of the housing, ay spring having one end anchored with respect to the housing and its other end connected to said housing, 'aV

brake band on the said .drum having one end secured to the housing and spaced from said drum and having its opposite end adapted to be pressed against the drum by the action of the strap on the housing. Y

3, A Vshock absorber comprising a brake drum adapted to be secured to one`l of two relatively movable vehiclemembers, a housing surrounding the said drum and spaced therefrom,a strap connected at one end to the exterior of said housing and adapted: to be connected at its other end 'to they vehicle member Aand arranged-to-engage the outer surface of the housing, a spring having one end anchoredwith respect to the housing and its other end connected to said li-ousing, and

- housing. t

LA shock absorber comprising a brake drum adapted to be secured to one of two relatively movable vehicle members, a housing surrounding the said drum and spaced therefrom, a strapV connected at one end to the exterior of said housing and adapted to be connected at its other end to the other vehicle member and arranged to engage the outer surface of the housing, a spring having one endanchored with respect to the housing and its other end connected to said housing, a

brake'band comprising an inner strip of frictionmaterial andan outer strip ofspring metal arranged to hold the first mentioned strip in engagement with the outer surface of the brake drum throughout the greater portion of theflengths of said strips, means for securing one end of the brake band to said housing adjacent to the point of attachment of the end of the strap to said-housing, such endiof the brake band being spaced from the brake drum, and a yieldable cushion carried by the opposite end of the brake band and substantiallyiilling the space between such end portion and the housing.

5. A shock absorber adapted vto beinterposed between two relatively movable vehicle members,the said shock absorber comprising a Ybrake drum having a vbase by means of which it'may be secured to one ,of said members, a housing surrounding the brake drum and enclosing the open end thereofand having an annular wall interposed between the youter portion of the base of the said drum and the vehicle member to which said drum is attached, the .said annular wall being provided with an annular recess projecting away from theA base-of said drum, a packing ring in said recess adapted to engage the base of saidl drum, a spring having one end anchored within the said vdrum and its opposite end secured to the cover portion of the said housing, a strap secured at one end to the exterior of the housingand bearing Ion the said housing, andaibrake band on the exterior surface of the brake drum and having. one end secured to the said housing and spaced from the brake drum and having its opposite end thickened thereby to engage both the brakedrumand the interior of the housing. ,6.r A. shock absorber adapted toev-be interfrom one end of the brake drum and a central- Vwall projecting outwardly from suchannular wall and adapted to be secured to one of the vehicle members, a disk adapted to be inter-V posed between the saidV central wall and the vehicle vmember to` which said wall is attached, the said disk' having a flanged periphery projecting toward suchannulaiwall but'spaced therefrom, a housing surrounding and spaced from the brake drum and having acover for the open end thereof and having an inwardly projecting annular wall adapted'to be inter-y posed between the annular wall of the base of the drum and the said disk, the said annular'housing wall having one or more annular recesses therein facing the annular wall 'of the brake drum, a packing ring in each suoli recess, a helical spring having one .end'an-Y chored within the rbrake drum'and having its oppositev endsecured to the housing cover, a strap secured at one end to the housing and engaging the outer surface of saidhousing, and a brake bandv interposed-between the said housing and the brake drum and adaptedto be operatively applied to the saidd'rum by movement of the housing with reference to the drum in` a direction opposed by the said spring.' y j' 7. The combination, with two relatively iriovable rvehicle members, of a' shock absorber comprising a brake drum secured to one of said members, a brake band onsaid drum, and flexible meansr connected with the other vehicle member and with one end of the brake band,the said flexible connecting means operating, during movements of the vehicie'inembers away from `each other, to press one end ofthe brake band against the drum with the opposite end Yof saidV band free and to release the pressurev on the first mentioned end ofthe brake-band when the vehicle membersfshall have moved apart a predetermined distance, and means for moving the brake band freely during movements of the vehicle members towardeach other.

i8, The combination,with/two relatively i'novable vehicle members, of a shock absorber 9. The combination, vwith two relatively movable vehicle members, of a shock absorber comprising a brake drum secured to oneof the said members, a brake band cooperating with said drum, and a flexible connection between the other vehicle member and the said brake band operating to cause the said band to exert a braking pressure against the drum during movements l of la predetermined amplitude of the vehicle members away from each other and to release such pressure when such amplitude shall have been exceeded as Well as during movements of the said vehicle members toward each other, and a spring connected with said brake band for moving the same and taking in the slack of said flexible connection during the latter movements of the vehicle members.

l0. The combination, with two relatively movable vehicle members, of a shock absorber comprising a brake drum secured to one of the said members, a brake band cooperating with said drum, and a flexible connection between the other vehicle member and the said brake band operating to cause the said band to exert a braking pressure against the drum during movements of a predetermined amplitude of the vehicle members away from each other and to release such pressure when such amplitude shall have been exceeded as well as during movements of the said vehicle members toward each other.

ll. The combination, with a pair of relatively movable vehicle members, of a brake drum secured to one of said members, a housing arranged concentricallywith respect to the said drum and spaced therefrom and movable toward and from said drum, a brake y band interposed between the said brake drum and housing and having one end adapted to engage both the drum and the housing and its opposite end secured to the housing and spaced from the drum, al flexible connection between the said drum and the other vehicle member, and a spring connected with said housing for moving the same and the brake band and for taking in the slack ofthe flexible connection when the vehicle members approach each other.

l2. The combination, with movable vehicle members, of a shock absorber comprising a brake drum secured to one ofv the said members, a brake band cooperating with said drum, and a flexible connection between the other .vehicle member and the said brake band operating to cause the said band to exert a braking pressure against the drum during movements of a predetermined amplitude of the vehicle members away from each other and to release such pressure when such amplitude shall have been exceeded.

13. The combination, with two relatively movable vehicle members, of a shock absorber comprising a brake drum secured to one of the sai-d members, a brake band cooperating with said drum, and a flexible connection between the other vehicle memberand one two relatively end of the said brake band and operating to force the opposite end ofthe brake band@ against the drum and cause the band to exert a braking pressure aga-inst the drum during movements of a predetermined amplitude of the vehicle members awayfrom each other` and to release such pressure when such amplitude shall have been exceeded.

In testimony whereof, yI hereunto afx my signature.

CLAUD H. FOSTER. 

